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ASHRAE 62.2-2010Red Calc Tool User Guide

What this tool can do for you

The ASHRAE 62.2-2010 RED Calc tool handles all the requirements of the
Standard, including new and existing buildings, the alternative compliance
path, and infiltration credit. We have added useful features, including the
advanced blower door inputs option and the fan-run time option for
intermittent operation of whole-building ventilation.

This tool complies with the requirements of the Department of Energy (DOE),
so you can use it with confidence.

ASHRAE 62.2-2010

Calculated values

Natural airflow.

Whole-building required airflow.

Alternative compliance supplement.

Infiltration credit.

Whole-building mechanical ventilation.

Fan run-time per hour.

Tips

Clicking the label for any input or result will cause a
popup help box to appear. This help box includes the
allowed and normal values (for inputs).
Read more.

Tool works for existing and new construction.

Weather data is included for the United States and Canada.

You may choose to use the Advanced Blower Door Inputs to adjust your results
for temperature, altitude, or pressure exponent.

You may choose to use the Local Ventilation Alternative Compliance feature
for existing dwellings. This feature includes one kitchen and from one to
five bathrooms.

The Whole-Building Ventilation Run Time tool allows you to determine run-time
per hour if you wish to operate the whole-building fan intermittently.

You may use this tool to comply with the ASHRAE 62.2-2007 Standard:
For new dwellings, simply select New for the choice “New or
existing construction”. For existing dwellings, select Existing
for the choice “New or existing construction”, select Yes or No for
“Use infiltration credit”, and make sure “Use Local Ventilation
Alternative Compliance” is not checked.

The ASHRAE 62.2 Standard is written as a minimum standard; you may exceed
the minimum requirements of the Standard.

Inputs and field measurements

Floor area - from site measurement or construction drawings. Area of the
livable floor space. Include basements only if they are chcaracterized
as living space within the pressure envelope.

Number of occupants - the number of bedrooms, plus one. For variation,
see ASHRAE 62.2-2010, Section 4.1.1.

Local ventilation alternative compliance - optional; measured existing fan flow
in kitchen and up to five bathrooms, openable windows in kitchen and
up to five bathrooms.

Background

Although the first version of the ASHRAE Standard 62.2, Ventilation and Acceptable
Indoor Air Quality in Low-Rise Residential Buildings, was published in 2003; the
2010 version was the first to gain national attention.

The Wisconsin low-income weatherization program was the first organization
to adopt the residential ventilation/IAQ standard, in late 2004. As of the
end of 2012, they had installed ASHRAE 62.2 ventilation in over 20,000 homes.

The adoption of the ventilation/IAQ standard gained momentum in 2011 when
the Department of Energy required the use of ASHRAE 62.2-2010 in the low-income
weatherization program by the end of the 2012 program year. In 2013 the
Building Performance Institute (BPI) adopted the 2013 version of the standard.

The adoption of ASHRAE 62.2 makes obsolete the use of the Building Tightness
Limit (BTL or BTLa), the Building Airflow Standard (BAS), and the Minimum
Ventilation Rate (MVR). These methods were based on the obsolete ASHRAE 62-1989
standard.

Best practices

The ASHRAE 62.2-2010 Standard allows the use of the alternative compliance
path (Appendix A of the Standard) for existing dwellings. This path allows compensation for deficits in
local ventilation (kitchens and bathrooms) by increasing the flow rate of
whole-building ventilation. Generally, use of this alternative path saves
money and installation time, but it might result in lower indoor air
quality. Whenever possible, do not us the alternative compliance path.

References

ASHRAE. ASHRAE Standard 62.2-2010: Ventilation and Acceptable Indoor Air
Quality in Low-Rise Residential Buildings. Atlanta, GA: American Society
of Heating, Refrigerating and Air-Conditioning Engineers, Inc. This document
may be purchased at www.ashrae.org.
Comment: This is the official standard upon witch the RED
Calc tool is based.

ASHRAE. 62.2 User's Manual. Atlanta, GA: American Society of
Heating, Refrigerating and Air-Conditioning Engineers, Inc. This document
may be purchased at
www.ashrae.org.
Comment: This document is based on ASHRAE 62.2-2010 and
includes many explanations and examples for field use.

ASHRAE. ASHRAE Guideline 24: Ventilation and Acceptable Indoor Air
Quality in Low-Rise Residential Buildings. Atlanta, GA: American Society
of Heating, Refrigerating and Air-Conditioning Engineers, Inc. This document
may be purchased at
www.ashrae.org.
Comment: This document is loosely based on ASHRAE 62.2-2010
and includes commentary and guidance on achieving acceptable indoor air quality
in low-rise residential buildings.

Raymer, Paul H. Residential Ventilation Handbook: Ventilation to Improve
Indoor Air Quality. New York: McGraw Hill, 2010.Comment: This is a very usable resource for the
understanding and installation of residential ventilation. Includes many
good illustrations, tables, and charts

Related tools

ASHRAE 62.2-2013 Ventilation:
Determine whole-building ventilation requirements for new and existing
dwellings, with the choice of using advanced blower door options and
the alternative compliance path.

Ventilation Electrical Usage:
Determine the annual electrical cost of operating a ventilation fan
that is set up for continuous or intermittent use.

Depressurization Analysis:
With this "solve-all" tool you can calculate house pressure, CFM50
tightness limit (Depressurization Tightness Limit), or total exhaust
fan flow.

Pitot Tube Airflow:
With this tool, a pitot tube, and a digital manometer, you can determine
the airflow of a ducted range hood, a clothes dryer, or other appliance
will an accessible duct.

Box Airflow:
Determine the flow of an exhaust fan with this tool, a cardboard box, and
your digital manometer.